LHAASO discussion session organized by COST Action CA18108 on 17th June

Event: LHAASO discussion session
Date: 17th June 2021, from 9 to 13 h (CET time)


Discussion session organized by the COST Action CA18108 “Quantum gravity phenomenology in the multi-messenger approach” ( the revolutionary detection of 12 PeVatrons (sources of very high energy gamma-rays) that the LHAASO collaboration has recently announced (Zhen Cao, F.A. Aharonian et al., Ultrahigh-Energy Photons up to 1.4 Petaelectronvolts from 12 γ-Ray Galactic Sources, Nature 594, 7861 (2021)) and its impact, especially with respect to LIV searches (see e.g., C. Li and B.-Q. Ma, Ultrahigh-Energy Photons from LHAASO as Probes of Lorentz Symmetry Violations, arXiv:2105.07967), which is one of the key topics of research within our Action. 

– 9:00 CET: Felix Aharonian: PeVatrons, theory
– 9:45 CET: Zhen Cao: LHAASO experiment results
– 10:30 CET: Bo-Qiang Ma: LIV with LHAASO
– 11:15 CET: Free discussion

In order to receive the link to this event, please register before 16th June, 14h CET time at the following indico page:

(Action participants who have already received the link do not need to register, but accept the invitation sent from e-COST)

CA18108 Action participants receive prize in the Gravity Research Foundation essay competition

We are proud to announce that the essay “Quantum Gravity Phenomenology in the Infrared”, (arXiv:2104.00802 [gr-qc]), which contributes to our COST CA18108 Action, has won the second prize in the Gravity Research Foundation essay competition.

Congratulations to the authors! From left to right in the photograph: Laurent Freidel (Perimeter Institute for Theoretical Physics, Canada), Jerzy Kowalski-Glikman (University of Wroclaw, Poland), Robert G. Leigh (University of Illinois, USA), and Djordje Minic (Virginia Tech, USA).

Action participants receive prize by the journal Universe within its Best Papers Awards 2015-2021


Action participants Diego Rubiera-García (UCM, Madrid, left photograph) and Gonzalo Olmo (IFIC, Valencia, right photograph) are among the winners of the Universe 2021 Best Paper Awards. The journal has selected their paper

Nonsingular Black Holes in ƒ (R) Theories
By: Gonzalo J. Olmo and Diego Rubiera-Garcia
Universe 20151(2), 173–185

as one of the three winning papers, after a thorough evaluation of the originality and significance of the papers, citations, and downloads.

The authors explain about their work:

“The paper Nonsingular Black Holes in ƒ(R) Theories studies the structure of a family of static, spherically symmetric space-times generated by an anisotropic fluid and governed by a quadratic ƒ(R) theory. We found solutions that represent black holes with the central singularity replaced by a finite size wormhole, and showed that time-like geodesics and null geodesics with nonzero angular momentum never reach the wormhole throat due to an infinite potential barrier. For null radial geodesics, it takes an infinite affine time to reach the wormhole. This means that the resulting space-time is geodesically complete and, therefore, nonsingular despite the generic existence of curvature divergences at the wormhole throat.”

Our congratulations to both researchers!

DSR20 online meeting

It’s now 20 years since the first Doubly Special Relativity papers appeared on ArXiv. Several research groups have worked on DSR-relativistic models, leading to significant progress, but some grey areas remain on the conceptual side and additional phenomenological avenues are much needed. The meeting “DSR20” (an online meeting, using zoom) intends to be an opportunity for an exchange of ideas on these matters. DSR20 will be held from december 14 to december 16 and it will be scheduled so to allow colleagues in different parts of the world to attend at least some of the sessions.

The registration form and additional information can be found at the following website:

New MC observers from Georgia Institute of Technology, USA, join CA18108

The Management Committee of CA18108 has approved the participation of  Prof Adam Nepomuk Otte and the PhD student Mr Alasdair Gent as MC Observers from Georgia Institute of Technology, USA. A description of the request can be found here. The complete international structure of COST Action CA18108 can be seen at this page in our website.

Workshop (WE-Heraeus-Seminar): Experimental Tests and Signatures of Modified and Quantum Gravity, 01 Feb – 05 Feb 2021

The aim of the meeting is the extend and foster the exchange between people working from theoretical and experimental side on the prediction and detection of modified and quantum gravity.

Further information can be found below and at

Two major unsolved questions in fundamental physics are related to the gravity: What is the nature of Dark Matter and Dark Energy, and, what is the theory of quantum gravity? From the theoretical point of view these questions stimulated various fundamental approaches to a theory of quantum gravity, such as string theory, loop quantum gravity, canonical quantum gravity, noncommutative geometry, asymptotic safety and others as well as phenomenological models such as doubly or deformed special relativity and the relative locality framework. Moreover, numerous classical modifications of General Relativity have been suggested such as scalar-tensor theories, f(R)-theories, bi-metric gravity, tensor-vector-scalar gravity or metric affine gravity, Poincare gauge theory, telleparallel gravity, Finsler gravity and many more.

The viability of these alternative or extended theories of gravity has to be tested by comparison of predictions with experimental data. It is important that this comparison is done on all scales from the whole universe, i.e. on cosmological scales, via galaxy-clusters, galaxies, binary systems, black holes, the solar system, satellite experiments, down to laboratory experiments at micrometer and smallest scales, i.e. high energy scales looking for new elementary particles like axions or WIMPs.
This seminar aims for discussing predictions and their comparison with experiments of extended and modified classical and quantum theories of gravity, on all scales. The goal is to identify theories, which are consistent on all scales, and, to identify observables, in which deviations of general relativity or the quantum nature of gravity is most likely to manifest itself.

Organizing Committee
Christian Pfeifer, Univeristy of Tartu, Estonia
Claus Laemmerzahl, University of Bremen, Germany

New MC observer from Universidad Autónoma de Chiapas (UNACH), Mexico, joins CA18108

The Management Committee of CA18108 has approved the participation of  Dr Humberto Martínez-Huerta as MC Observer from Universidad Autónoma de Chiapas (UNACH). A description of the request can be found here.

Mexico participates in our Action with researchers from two institutions, Universidad Autónoma de Chiapas (UNACH) and Universidad Nacional Autónoma de México (ICN-UNAM). The complete international structure of COST Action CA18108 can be seen at this page in our website.

Interview with CA18108 Action participant Antonio Ferreiro on his research on quantum effects in curved spacetimes and the additional challenges faced by the LGBT+ community in fundamental theoretical physics

In the Twilight between General Relativity and Quantum Theory

Antonio Ferreiro on his research on quantum effects in curved spacetimes and the additional challenges faced by the LGBT+  community in fundamental theoretical physics

Antonio Ferreiro is a fourth year PhD student at the University of Valencia and the Instituto de Física Corpuscular, a joint centre between the Spanish Research Council and the University of Valencia devoted to research in Nuclear, Particle and Astroparticle Physics. Ferreiro is a member of the Working Group 1 of the COST action on quantum gravity phenomenology in the multi-messenger approach. He is interested in the big questions about our universe: What is dark matter? What came before the Big Bang? Can we understand Quantum Theory in curved spacetime?

In particular he is interested in understanding Quantum Field Theories in curved spacetimes. One of the biggest challenges is the fact that Quantum Field Theories and General Relativity do not fit together smoothly. He studies what the correct coupling between matter and spacetime is in the semi classical setting, where matter is modeled by Quantum Field Theory  and spacetime is treated as a classical solution of General Relativity. These questions are of particular interest in the early universe where the matter density becomes large and our classical theories become inadequate as quantum fluctuations from the earliest moments of our universe form the seeds for all the structures that will develop in the future evolution of the universe. 

Besides the BSc and MSc degrees in Physics which Ferreiro did in Valencia he also completed a master in Philosophy of Science at UNED (Universidad Nacional de Educación a Distancia, the National Distance Education University of Spain). Ferreiro is also active in science communication activities. Further, he is an active member of the LGBT+ community focusing on the fight against discrimination. For many years he was part of the LGBT+ association of Valencia and recently, together with students from the faculty of physics, he founded the first LGBT+ association of the science campus of the University. 

In the context of the LGBT+ pride day, the COST QG-MM action outreach team conducted a written interview with Ferreiro about his research and his experience with discimination in academia.

COST QG-MM action outreach team: What do you hope to contribute with your research to our understanding of fundamental physics?

My work focuses mainly on the problems that arise when we try to merge general relativity and quantum field theory. This is especially important since without the correct construction of the theory we are not able to predict properties of the cosmos which are testable by observations. In addition, my research could give rise to  a better understanding of the physics of the early Universe physics such as inflation, a short period of rapid expansion in the very early universe. I also want to contribute to our  understanding of the vacuum energy density and its imprint in the accelerated expansion of the Universe that we observe today. 

COST QG-MM action outreach team: During your PhD you already (Co-) autored 10 research papers. Which is your favourite one and why?

 I would say the most recent one on “Running gravitational couplings, decoupling, and curved spacetime renormalization”. It was by far the most entertaining one because I was really intrigued about the vacuum energy density and the relation with the cosmological constant problem. I spent a lot of time studying the literature and not only got to understand the general problem but also to contribute to a better understanding of it. It was also satisfactory to have made use of not only my knowledge about quantum field theory in curved spacetime but also my background (Master degree mostly) in particle physics where my institute is really strong at. 

COST QG-MM action outreach team: Besides your degrees in Physics you also completed a Master in Philosophy of Science. What motivated you to do this extra degree? 

I think that historically there is a strong relationship between physics and philosophy but, due to the current specialization, it is really difficult to go out of the box on your research topic. I wanted to understand science from another perspective and this master gave me the opportunity as I was able to study the problems of the scientific method, the philosophical problems in physics and also, one of my favourite topics, the social understanding of science. My master thesis was about the relation between science and democracy and how can we learn from both sides to improve the conditions in the science community and also in society. 

COST QG-MM action outreach team: What was your motivation to pursue a research career in fundamental theoretical physics?

For me, the most attractive feature of fundamental physics is  that you can completely understand (or at least try to!) some very exotic phenomena from the most basic theories. It is very fascinating to me to get to know the world you live in through mathematical equations and from rigorous physical theories. 

COST QG-MM action outreach team: When did you decide that you would want to do research in fundamental theoretical physics? 

In my erasmus year at the University of Bonn I did some courses in cosmology and astrophysics and when I came back to Spain I really enjoyed the quantum field theory course that I had in the degree. In my last year of physics, when I found out that the group of my supervisor, Jose (Pepe)  Navarro-Salas, was focused in the relation between this two field, I did not hesitate to lead my research in this direction and did my degrees and master thesis with Pepe and now I am also doing my Phd with him. 

COST QG-MM action outreach team: What obstacles did you face on the way to your PhD?

I think that the biggest obstacle is to be mentally prepared to confront some problems that you usually will not face in other jobs. For example, to be prepared to fail and have some epochs where you are not going to produce anything fruitful. Also the uncertainty of the research career is also a big problem that you have to be aware of. I had luck to have an outstanding supervisor and very good colleagues that helped me overcome most of these problems.

COST QG-MM action outreach team: You told us that you are an active advocate for the LGTBQI community. Can you tell us about your experience with discrimination in academia?

I will only talk about my experience, since as a cis white men I do not face the same amount of discrimination as other groups (trans people, non-binary, women, etc.) do. I do not feel that there is a explicit discrimination as there is maybe present in other careers. However, in my case the importance of internationalization of the scientific career is a big obstacle. I remember being with some colleagues at a table and some professor asked if we would do postdocs in any country of the world or if we had any  requirements. Most colleagues answered affirmative but I couldn’t. We cannot forget that there are still plenty of countries where my sexual orientation is illegal or not socially accepted. It is even worse at the initial stages of your career because maybe you can find a department that is a real safe space for you but then next year you are forced to go to another one where this condition is no longer ensured. 

This is also relevant when we have to go to conferences or summer schools. In many of these occasions members of the LGBT+ community have to “get into the closet” again.  In particular, I believe it is even more difficult for trans and non-binary people. Most of the application forms assume the usual women/men distinction, not assuming other identities and the possibility that trans people do not often have their official documents updated with their gender and names. This seems maybe a trivial issue but adding the usual discrimination that these groups suffer it can decrease the possibilities for members of the LGBT+ community to perform at their maximum level of capacities and have equal opportunities. 

COST QG-MM action outreach team: What do you think are the most urgent measures that need to be implemented by the fundamental theoretical physics community to address the problem with discrimination of LGBT+ people in the field?

For me, it is especially important to make the departments a safe space for the LGBT+ community. For example, my institute has an office that focuses on possible discriminations that can happen there. I think there should be special protocols for homophobic and transphobic discrimination at each University and research institute. For example, let’s assume that you begin your phd with a supervisor that do have homophobic or transphobic atitudes. It is currently very difficult to overcome this problem since you are attached to him/her for at least three years and taking actions could maybe cost you your research career. 

There are also bureaucratic problems that I have already mentioned. First, the traditional application forms that assume your assigned gender identity. Also summer schools and other scientific gatherings where the youngest researchers maybe need to share accommodations with other Phd students from other countries lacks from protocols that include the possibilities of being trans or non-binary. 

In any case, since this is only my opinion, I highly encourage all scientists, but specifically organizers and Principal Investigators to inform themselves about  the common problems that the LGBT+ community faces. In Spain for example, there exists a Science LGBT+ association ( ) where one can find  a lot of information about these issues. 

COST QG-MM action outreach team: You are close to the end of your PhD, what are your further plans? Where do you want to make your next step, what are your career ambitions in the long run?

I would really enjoy continuing my research career as a postdoc. However, I am conscious of the difficulties of having a stable career in this field. So I actually can not give a definitive answer to this question. My options range from doing a postdoc, over doing a Phd in philosophy of science to go into teaching. Maybe I can give you an answer next year.  

Interview by Claudio Paganini

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